flutter_twain_scanner

A Flutter plugin that enables you to develop Windows desktop applications for digitizing documents using TWAIN, WIA, and eSCL scanners. The plugin offers callable methods for both open-source TWAIN (64-bit only) and the Dynamsoft Service REST API, supporting 32-bit and 64-bit TWAIN, WIA, and eSCL scanners.

Dynamsoft Service REST API

By default, the REST API's host address is set to http://127.0.0.1:18622.

Method	Endpoint	Description	Parameters	Response
GET	/DWTAPI/Scanners	Get a list of scanners	None	200 OK with scanner list
POST	/DWTAPI/ScanJobs	Creates a scan job	license, device, config	201 Created with job ID
GET	/DWTAPI/ScanJobs/:id/NextDocument	Retrieves a document image	id: Job ID	200 OK with image stream
DELETE	/DWTAPI/ScanJobs/:id	Deletes a scan job	id: Job ID	200 OK

To make Dynamsoft Service work:

1. Install Dynamsoft Service REST Preview for Windows.
2. Request a free trial license.

API Usage

Open Source TWAIN

• Future<List<String>> getDataSources(): Get the list of TWAIN compatible scanners.

  List<String> scanners = await _flutterTwainScannerPlugin.getDataSources();
  

• Future<List<String>> scanDocument(int sourceIndex): Scan documents from a selected scanner.

  int index = _scanners.indexOf(_selectedScanner!);
  List<String> documentPaths = await _flutterTwainScannerPlugin.scanDocument(index);
  

Dynamsoft Service

• Future<List<dynamic>> getDevices(String host, [int? scannerType]): Get the list of TWAIN, WIA, and eSCL compatible scanners.

  String host = 'http://127.0.0.1:18622';
  final scanners = await dynamsoftService.getDevices(host, ScannerType.TWAINSCANNER | ScannerType.TWAINX64SCANNER);
  

• Future<void> deleteJob(String host, String jobId): Deletes a scan job based on the provided job ID.

  await dynamsoftService.deleteJob(host, jobId);
  

• Future<List<String>> getImageFiles(String host, String jobId, String directory): Saves images from a scan job to a directory.

  List<Uint8List> paths =
          await dynamsoftService.getImageFiles(host, jobId, './');
  

• Future<List<Uint8List>> getImageStreams(String host, String jobId): Retrieves image streams from a scan job.

  List<Uint8List> paths =
          await dynamsoftService.getImageStreams(host, jobId);
  

• Future<String> scanDocument(String host, Map<String, dynamic> parameters): Creates a new scan job using provided parameters.

  final Map<String, dynamic> parameters = {
    'license':
        'LICENSE-KEY',
    'device': devices[index]['device'],
  };
  
  parameters['config'] = {
    'IfShowUI': false,
    'PixelType': 2,
    'Resolution': 200,
    'IfFeederEnabled': false,
    'IfDuplexEnabled': false,
  };
    
  final String jobId =
        await dynamsoftService.scanDocument(host, parameters);
  

  The parameter configuration is based on Dynamsoft Web TWAIN documentation. It controls the behavior of the scanner.

Libraries

dynamsoft_service

flutter_twain_scanner

flutter_twain_scanner_method_channel

flutter_twain_scanner_platform_interface